The Hedegehogs are a popular band that both Yuu Haruna and Koyuki Hinashi are fans of. Sometime during the manga, the band decided to disband upon Tama losing her voice. Later, they pass on their inspirations to the Fallen Moon and their later incarnation, Blue Wells, letting them use their former studio for practice.
- Tama Reika - Vocalist
- Musashi Nicholsen Oda/Nico - Bassist
- Nobuaki Yahagi/Nobu/Yassan - Drummer
- Tomomi Yoshino - Keyboard
- Hisashi Iwami - Guitarist